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Topic: 'EY' coil springs.. update (Read 5166 times)

A few months ago, I was dismantling my front suspensioni for rebuilding, intending to just clean and replace ball joints/bushings/rubber... but ALAS.. I found one loop of one of my springs was broken (the bottom loop.. still lying in the bottom of the cup). When I got them out, i also found both springs still had their original 'EY' factory tapes on them, so at least I knew what I needed. I spent a couple of weeks looking .. ordered what was supposed to be the original replacement (MOOG) .. tried two different spring numbers recommended here and in TC.. but neither of them even *looked* like the springs I removed (wrong number of coils, different wire dia etc). When I requested help, Steve Shauger recommended I contact Coil Spring Specialties (Lenexa, KS).. so I did. They do custom springs for just about any application. I sent them my one good original spring, and we had many discussions on the phone and via email over a couple of months. My concerns were that the replacements... 1) had the same number of coil loops (2) had as close as possible to the same wire thickness and free length (equivalent)3) Had at least the equivalent spring rate (new 340 lbs/in vs 320 measured on the old one)4) Sat no higher than my origiinal spring when static loaded in the car - yet to be checked.

Today, I finally received the springs via Fedex. Cost me $209, plus shipping my spring out there, which is more than twice the cost of the *replacement MOOG numbers* via Autozone/Advance/etc, BUT... the springs LOOK like my original spring. See photos of the two new springs flanking the original spring! The only remaining things to do is to assemble the front suspension, reinstall ALL the parts I've removed for cleaning.. ... and check the ride height! I'll let you fellas know how it works out. In the meantime, if anyone else wants to duplicate the original EY spring, Coil Spring Specialities has the data now from measuring my spring and producing my new springs.. so it should be lots easier/faster and cheaper for them to pop a couple off for you. OR you can wait to see how mine work out..

PS. I asked them not to paint the springs, so they are bare steel right now. Should I clear coat them? or ??

Gary, not to rain on your parade, and I hope everything works out for you, but when springs get old and worn, they expand. Up to several inches! If you had them make the new springs based on the length of your old springs (as it appears they did from your pictures), then your car is going to ride a lot higher in the front then when it was new. Of course, this is based on how bad your original springs were, but you can pretty much bet that 40 year old springs are worn out.

Ed,The important parameters when talking to the coil spring mfg is front end weight and 'installed spring height', and when I was researching for the replacement springs, I found GM information on the front end weight for my options, but could not find documented values for the compressed spring height (for a Z28). I literally spent months and dozens of phone calls and discussions with the mfg before we settled on the spring parameters.

From my memory, I recall original Z28's sat lower in front than say an SS or other similar camaros, but I have not been able to find a value for that from any GM literature or from any posts here or in TC. The spring manufacturer used 10" for that value and made the springs so that for the GM documented weight on the front end of my car, it should compress the spring to 10". I HOPE that value is correct.. time will tell when I get them installed and everything back on my car...

From my memory, I recall original Z28's sat lower in front than say an SS or other similar camaros, but I have not been able to find a value for that from any GM literature or from any posts here or in TC.

The info you need is in the AIM. UPC 0, sheet A10. Dimension "Z" for the Z28 is 1.93" (curb weight), or about a half inch lower than a non-Z. Dimension "J" however (33 inches aft of the center line of the front wheel), is just about the same as the non-Z, so yes, the Z sits lower at the front than a non-Z, but it's really not by much. Same thing goes for the rear of the Z. It's a little lower than a non-Z, but not by much.

I was unable to find any springs which matched in appearance, coil wire thickness, and number of coils to the original EY springs.. I went to more trouble, more time, and more $$ in trying to match up the physical characteristics as well as the functional characteristics. My original EY springs had 8-1/8 loops, and were ~0.60" wire size. I haven't yet got the weight back on these springs to check static height, so that is my last question to be answered.

When i got my springs i called hbc on their yf springs. They don't sell the exact springs anymore. They sold me the small block springs. My car sat like the engine was out. Spring waS like 3 inches longthemer. pozzi racing has a Web site where he tested alot of moog springs and i got a set to match the z. Very happy with them. His site had alot of good info

I talked to all the suppliers, even bought a couple of sets of springs as recommended. None of them even came close to matching the appearance (number of coils,etc) so I was not going to iistall them... now, if these springs don't make my car sit/ride right, then I might have to go wtih one of the others, but first I wanted to try with a matched appearance spring. I'll update when I get some weight on my front end...

I have a pair of front springs from a 69 Z. I don't know if they are EY springs or YF springs. Pretty certain they are not YH. I sand blasted and painted them many years ago. I do know for certain they were original springs on a Z. Just don't know what options that Z had, because at the time, I thought all the Z's got the same front springs, so I never asked. They are not the originals off my car that are mia.

Wire diameter is .580 to .585 depending on where you measure.

Just over 8 coils.

Gary, are you certain your original EY spring is .600?

I also have a question regarding usage of the spring chart. Options on my car include am fm radio (+6lbs), VE3 bumber (-6) spoilers (-1) and ducted hood (+1 if I read the chart right). Add that together and it is 0.

Anyway, do you figure in additional weight for power brakes and four speed since they were mandatory?Even figuring those two in (11 and 9), I am under the 68 lbs it takes to get to a EY spring.

I mic'ed them at 0.595 .. that was after bead blasting, so I figured they lost 0.005 to 'rust' over the years. *L*My car is an RS with ZL-2 hood vinyl top.. custom interior.. rem mirror... trying to recall the heavy options... RS was the biggie I think? my total went about 65-90 lbs over if I recall...

I have the suspension back together; had to sit the engine/trans in place to compress the springs sufficently to hook up the ball joints. Just for kicks (and an early indication of where these springs are going to sit), I took it off the jack stands and put it on the tires yesterday. As you can see from the photo, there are still a LOT of things not installed, so hopefully the front will settle down another inch or so. I measured the height of the bottom of rocker at the front and at the rear and got 10-3/8" and 9-3/8" respectively. The designed in load rate for the springs are 370 lbs/in. I probably need for the missing parts on the front to total 450-500 lbs to get the height where I want it. The rear should also go down a bit with gas in the tank and spare/jack/etc in the trunk. The car is an RS with cowl hood and dhrome/steel bumper. the Photo shows all the stuff that's missing still off the front end. If anyone has a feel for how much it all weighs, I'd love to hear it.

I am looking for front coils for a 69 Z as well. I have a set of springs from a friends 69 Z. He pulled his springs out to change his ball joints. When he put the springs back in the car it sat much higher in the front. As a result he ordered new front coils that were dropped one inch, from Eaton I think. The car sits perfect now. I was going to use his old springs as I am installing new leaf springs, and I thought they would balance out. Is it possible the expansion occurred when he removed the coils and should I get new coils? I don't want to install his old coils only to have to remove them and get new ones. I would rather just do it once while it is all apart.